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1.
Six phytoecdysterones have been isolated from the n -BuOH portion of Cucubalus baccifer L., a Chinese folk medicinal plant. Their structures were elucidated as ecdysterone (1), 24(28)-ecdysterone (2), 22-deoxyecdysterone (3), 25-hydroxypanuosterone (4), rubrosterone (5) and 2,22-dideoxyecdysterone 3β-O-β- D -glucopyranoside (6) respectively on the basis of spectroscopic and chemical methods. Among them compound 6 was a new phytoecdysterone glycoside and 1-5 were first obtained from this plant.  相似文献   

2.
This paper is a systematic report on a collection of caddisflies from Papua‐New Guinea. Twenty‐four taxa are identified to species and nine others are determined only to the generic level. Te new species (Diplectrona papuana n. sp., D. subtriangulaia n. sp., Herbertorossia kimminsi n. sp., Hydropsyche papuana n. sp., Cheumatopsyche beroni n. sp., Polycentropus mounthageni n. sp., P. elegans n. sp., Polyplectropus chapmani n. sp., Oecetis kimminsi n. sp. and Triaenodes lelefominicus n.sp.)and the females of Polycentropus similis Kimm, and Polycentropus sinuosus Kimm, are described. New faunistic data is presented for the other species which is supplemented in a few cases by taxonomic notes. The genera Cheumatopsyche, Polyplectropus and Nyctiophylax are new to the fauna of New Guinea.  相似文献   

3.
α-(Hydroxymethyl)serine was isolated and characterized from the seeds of Vicia pseudo-orobus (Leguminosae).  相似文献   

4.
5.
Agars from three species of Gracilaria (Rhodophyta) from Yucatán Peninsula   总被引:2,自引:0,他引:2  
Gracilaria cervicornis, Gracilaria blodgettii and Gracilaria crassissima growing along the coasts of Yucatán were investigated for their agar content. The effect of different concentrations of NaOH in the alkali treatment was evaluated. The three species of Gracilaria produced agars, both native and alkali treated, with different properties confirming the heterogeneity of the agar polymers in this genera. G. cervicornis produces agar polymers with an occurrence of methoxylation and sulphation at the C-6 of the beta-D-galactose residues, and with an extra methylation due to the presence of the 4-O-methyl-alpha-L-galactose residue. The presences of these residues is responsible for the extremely poor gelling ability of its agarocolloids, whose commercial value seems to be quite low. Agar extracts from G. blodgettii showed the typical pattern of unsubstituted agar with a very low degree of methylation on both galactose residues. The discrepancy found between sulphate content and NMR data of agar from this species requires a more detailed structural investigation. G. crassissima produces a good quality agar after sulphate precursor sequences have been removed by alkaline treatment, and it may be considered for exploitation as a source of commercial grade agar. Alkali treatment was effective both in removing alkali-labile sulphate and increasing the gel strength in G. crassissima but not in G. cervicornis and G. blodgettii.  相似文献   

6.
A new genus and species, Espanoderus barbarae gen. et sp. nov., belonging to the family Tanyderidae (Diptera, Nematocera), is described from Lower Cretaceous amber of Spain (Álava amber). The new genus is the smallest member of Tanyderinae and the first member of the family from the Álava amber. The position of the new genus in a phylogenetic tree of Tanyderidae is presented.

http://zoobank.org/urn:lsid:zoobank.org:pub:EC3284BA-C07F-48AC-8AF5-4F9D2EF4EA6C  相似文献   


7.
The changes in α-galactosidase activity in guar (Cyamopsis tetragonolobus) seeds was followed during seven days of germination. The enzyme activity was maximal on the first day of germination and gradually decreased during subsequent days. On the second day of germination the partially purified enzyme upon ion-exchange chromatography on CM-Sephadex C-50 was resolved into α-galactosidase-A (anionic), α-galactosidase-C1 (cationic) and α-galactosidase-C2 (cationic) and their relative proportions were 28,12 and 60%, respectively. The combined α-galactosidase C1 and C2 activities increased in the first two days of germination followed by significant decrease after the 3rd day onwards, whereas α-galactosidase-A remained fairly constant throughout the germination period, α-Galactosidase-A and C2 had differentK m and Vmax values withp-nitrophenyl α-D-galactopyranoside, raffinose and melibiose as substrates and also differed in their thermal stabilities  相似文献   

8.
Forty-seven taxa of Pyrenomycetes sensu lato from Almería, southern Spain, have been studied. The following are new records for the Spanish mycobiota: Capronia inconspicua, Comoclathris planispora, Diaporthopsis trinucleata, Eutypa consobrina, Eutypella kochiana, Montagnula longipes, Montagnula infernalis, Mycosphaerella nicotianae, Nectriella jucunda, Phaeosphaeria phragmitis, Pleospora dichromatricha, Pleospora rudis, Pleospora subalpina, Teichospora opuntiae and Trematosphaeria endoxyloides. Two new species are also described: Diademosa sabulosa and Phaeosphaeria rubescens.  相似文献   

9.
From January 2010 to December 2011, a total of 138 cases of ticks feeding on humans were reported from 11 locations in central Panama. Five of these locations were situated in forest environments, three in rural landscapes and three in urban areas. The ticks were submitted to the Gorgas Memorial Institute, where nine species were identified among 65 specimens: Amblyomma cajennense s.l., A. dissimile, A. naponense, A. oblongoguttatum, A. ovale, A. sabanerae, A. tapirellum, Haemaphysalis juxtakochi and Rhipicephalus sanguineus s.l. The remaining 73 specimens consisted of unidentified immature ticks, all belonging to the genus of Amblyomma. Rhipicephalus sanguineus s.l. was the species most frequently associated with humans, particularly in urban environments. In rural landscapes, tick bites were most often caused by A. cajennense s.l., whereas A. tapirellum was the species most often found parasitizing humans in forest environments. These data provide information on the tick species most commonly associated with humans in forested environments, rural areas and cities around the Panama Canal.  相似文献   

10.
The pattern of genetic variation of the lizard Mabuya maculilabris from S?o Tomé Island (Gulf of Guinea) was investigated using a combination of three mitochondrial DNA gene fragments. Forty-eight haplotypes were recovered among 66 individuals covering the whole island. The genealogy inferred from the most parsimonious network of haplotypes allows us to detect two main and long branches departing from the putative group of oldest haplotypes. The tips of these branches exhibit star-like phylogenies, which may indicate of recently expanded populations, most probably from a small number of founders. A nested clade analysis suggests a complex pattern of past events that gave rise to the extant geographical pattern found in the haplotype distribution: past and allopatric fragmentation, range expansion, restricted gene flow and long-distance dispersal. These results are consistent with the complex geological history of the island where important volcanic activity with extensive lava flows has occurred during several periods. Mismatch-distribution analysis and AMOVA also support these conclusions. Substantial genetic structuring among these lizards was detected as well as high levels of differentiation between the southern edge populations (particularly those from the Rolas Islet) and the remaining ones. However, variation is low relative to the geological age of the island. Our results indicate that patterns of variation observed in reptiles in other oceanic islands are not indicative of those observed in the islands of the Gulf of Guinea.  相似文献   

11.
A new lignan, named (—)-massoniresinol, has been isolated from Pinus massoniana needles. Its structure has been proved to be (2R,3S,4R)-3,4-dihydroxy-2-(4-hydroxy-3-methoxyphenyl)-4-(4-hydroxy-3-methoxybenzyl)-3-tetrahydrofuranmethanol by 1H NMR, 13C NMR, mass and CD spectroscopy.  相似文献   

12.
Aquatic habitats in the Republic of Panamá were examined for freshwater sponges during 21 Feb. to 6 March 1986. Eunapius carteri, Trochospongilla leidyi, and Trochospongilla horrida were found in the northern canal area. This is the first report of E. carteri and T. horrida from Central America, and the first record of E. carteri from the Western Hemisphere. Taxonomic characters used to distinguish T. leidyi and T. horrida from similar South American species are discussed.  相似文献   

13.
The mammalian fauna from Gülpinar (Canakkale, Turkey), dated Turolian, comprises threeHipparion taxa:H. cf.matthewi, H. sp. medium-sized, andH. sp. large. Two metatarsals may represent a fourth taxon or may derive from a different locality. The hipparion material is described here.  相似文献   

14.
Clestobothrium neglectum (Lönnberg, 1893) n. comb. is redescribed from specimens previously deposited in The Natural History Museum, London, UK by Dr David I. Gibson obtained from the intestine of the tadpole fish Raniceps raninus (Gadidae) collected from off the western coast of Sweden, near Kristineberg. C. neglectum resembles C. crassiceps (Rudolphi, 1819), the type- and only species currently recognised in the genus, but differs in having fine spiniform-like structures that are likely microtriches covering the posterior fourth of the scolex and all proglottids, a highly folded tegument forming numerous longitudinal ridges on both the dorsal and ventral surfaces of the proglottids giving them a scalloped appearance, a somewhat smaller egg (68 × 35 vs 75 × 40 μm), a U-shaped rather than H-shaped ovary and more testes (70–85 vs 40–50 per proglottid). C. neglectum is also compared to two species with similar scoleces that were previously assigned to Clestobothrium, Bothriocephalus acheilognathi Yamaguti, 1934 and B. kivuensis Baer &; Fain, 1958 (considered to be synonymous with B. acheilognathi by Pool, 1987). This is the first report of a species of Clestobothrium Lühe, 1899 (Bothriocephalidae) from a gadid fish.  相似文献   

15.
The Ediacaran–Fortunian ichnofauna from Central Brittany (NW France) is revised for the first time since the pioneering work by Lebesconte at the end of the 19th century. The study is based on fossils from the type-localities of the historical Brioverian taxa Montfortia (traces from Montfort-sur-Meu) and Neantia (wrinkle surfaces from Néant-sur-Yvel), and on two new outcrops from Saint-Gonlay. The ichnofossil assemblage includes Helminthoidichnites tenuis, Helminthopsis tenuis, Gordia marina, Palaeophycus tubularis, ?Neonereites uniserialis, and ?Spirodesmos archimedeus. Locally, the grazing traces are associated with wrinkle surfaces considered as microbially induced sedimentary structures (MISS). The sedimentological characteristics of these deposits correspond to a shelf marine environment. Both U-Pb datings on detrital zircon and ichnostratigraphic criteria tend toward an Ediacaran age of the fossiliferous deposits, but we cannot exclude the possibility of a Fortunian age at the present state of knowledge.  相似文献   

16.
In the course of an oxidative burst oxygen free radicals and hypothiocyanite (OSCN), a transiently abundant derivative of thiocyanate (SCN), are formed in the presence of activated polymorphonuclear leukocytes (PMNs). At the same time Cu(I)-thionein is present and the question arose whether or not thiocyanate and its oxidized form may transiently release highly Fenton active copper to improve the efficacy of the above mentioned oxidative burst. Thus, the reaction of yeast Cu-thionein with OSCN was examined. Indeed, a release of copper from the Cu(I)-thiolate clusters of the protein was observed ex vivo. Both the chiroptic and luminescence emission signals of Cu-thionein essentially levelled off in the presence of a 15-fold molar excess of OSCN expressed per equivalent of thionein-copper. The effective copper-releasing activity of this reagent was confirmed by equilibrium dialysis. The demetallized protein could be reconstituted under reductive conditions. SCN did not affect the copper-thiolate bonding. It rather acts as a potent metabolic source for the transient copper release from Cu-thionein in the presence of activated PMNs.  相似文献   

17.
  • 1.1. Rhizostoma pulmo, Aurelia aurita and Actinia equina, the most widespread representatives of Coelenterata in Black Sea have been analysed and the occurrence of 20 sterols has been found.
  • 2.2. Dinosterol and demethyldinosterol as well as a number of short side chain sterols have been found in Scyphozoa for the first time.
  • 3.3. The occurrence of coprostanol in marine invertebrates has been shown for the first time.
  • 4.4. Five groups of sterol esters were found, containing fatty acids with different polarity.
  相似文献   

18.
The component subunits of the pro-(carboxypeptidase A)–pro-(proteinase E) binary complex from pig pancreas were separated with a high recovery (80–95%) of their original potential activity. The isolated subunits and the reconstituted complex have properties similar to those of the corresponding natural species. The tryptic activation course of the pro-(carboxypeptidase A) subunit is substantially modified when bound to pro-(proteinase E), whereas the activation of pro-(proteinase E) is not dependent on this association.  相似文献   

19.
Upper Jurassic (Kimmeridgian) limestones of central Poland (southern border of the ?ód? Depression) are in places extremely rich in crinoid remains. These latter are represented by very well preserved columnals/pluri-columnals, isolated brachials and cirrals/pluri-cirrals, assignable to the following species: Isocrinus amblyscalaris (Thurmann, in Thurmann and Éttalon), Isocrinus cf. pendulus (von Meyer), Balanocrinus brachiospina Hess, Balanocrinus pentagonalis (Goldfuss), Balanocrinus subteres (Münster, in Goldfuss), Balanocrinus sp., and Millericrinida indet. The commonest species, Balanocrinus brachiospina, is recorded for the first time from Poland. Critical revision of Polish occurrence of balanocrinids is provided. It is suggested that some of the previous balanocrinid finds from Poland assigned to Balanocrinus subteres should be now addressed as Bbrachiospina. Furthermore, it is probable that the Callovian Bhessi Salamon and Zatoń should be synonymized with Bpentagonalis. Crinoid material at hand is also associated with asteroid and echinoid remains. Among this material, a complete test of Pleurodiadema nudum Cotteau is illustrated for the first time from Poland. Taphonomic observations of echinoderms from the Kimmeridgian limestones of the ?ód? Depression suggest that they did not undergo a long post-mortem transport. The high degree of disarticulation, however, supports their prolonged post-mortem seafloor exposure.  相似文献   

20.
P. (C.) cyclus sp. n. and P. (C.) jii sp. n. are described as male imagines. P. (C.) kamotertium Sasa and P. (C.) okigrandis Sasa are new records to China. A key to known adult males of the subgenus is presented. The subgeneric diagnosis is emended.  相似文献   

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